Adding rear disc brakes
02-08-2016, 11:01 AM
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Car: 1987 Trans AM
Engine: 355 4-bolt, L98 heads, Holley 650DP
Transmission: 700R4
Axle/Gears: 3.70 9-bolt
Adding rear disc brakes
I currently have a stock 10 bolt open rear with drums. I'm going to be installing a 9 bolt I just picked up after I get done rebuilding it. That means I'll be swapping out the drums with discs. What do I need? I have a proportioning valve but what else? I have rotors and calipers so far.
02-08-2016, 11:46 AM
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Car: 87 Iroc 5.7,67 SS Camaro,90 Formula
Engine: 355 AFR Superram LPE 219
Transmission: 700r4 3000 stall 4spd 5 spd
Axle/Gears: 3.27
Re: Adding rear disc brakes
i'm doing the same thing I have 2 cars 1 9bolt going in the other has a 10 bolt w discs going in. Thanks for the info in advance guys
02-08-2016, 07:15 PM
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Re: Adding rear disc brakes
If all you have is rotors and calipers, you're a ways off yet.
If the calipers are cast iron, don't bother.
If they're aluminum, they're worth tracking down the other parts for. You'll need backing plates and caliper "abutments", parking brake lines, and fluid lines.
If your calipers are the cast-iron ones, your brakes will probably work worse than your drums, after doing what it takes to install them. Spend money to shoot yourself in the foot in other words. Sell em to the next "greater fool" and start looking for the aluminum (PBR) setup instead.
If the calipers are cast iron, don't bother.
If they're aluminum, they're worth tracking down the other parts for. You'll need backing plates and caliper "abutments", parking brake lines, and fluid lines.
If your calipers are the cast-iron ones, your brakes will probably work worse than your drums, after doing what it takes to install them. Spend money to shoot yourself in the foot in other words. Sell em to the next "greater fool" and start looking for the aluminum (PBR) setup instead.
02-09-2016, 06:41 AM
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Car: 1987 Trans AM
Engine: 355 4-bolt, L98 heads, Holley 650DP
Transmission: 700R4
Axle/Gears: 3.70 9-bolt
Re: Adding rear disc brakes
While I appreciate the sarcasm its not helping me much. I have the iron calipers. I already have a rebuild kit, 3.70 gears, axle seals and wheel bearings ordered for this rear. So I'm not selling it to the "next greater fool".
I have the hard line and one rubber line for the calipers. I found a new set of brake lines and the PBR calipers. Its a bit more than I originally wanted to spend but it is what it is. Now if I buy the PBR calipers do I need to buy any adapter plates or will they bolt up to the stock brackets? Also you mentioned parking brake cable. Some have said I have to replace that and others have said the OEM one will work.
I guess to recap, I should get the PBR calipers, new rotors, new brake lines, and possibly a parking brake setup? Is that it?
I have the hard line and one rubber line for the calipers. I found a new set of brake lines and the PBR calipers. Its a bit more than I originally wanted to spend but it is what it is. Now if I buy the PBR calipers do I need to buy any adapter plates or will they bolt up to the stock brackets? Also you mentioned parking brake cable. Some have said I have to replace that and others have said the OEM one will work.
I guess to recap, I should get the PBR calipers, new rotors, new brake lines, and possibly a parking brake setup? Is that it?
If all you have is rotors and calipers, you're a ways off yet.
If the calipers are cast iron, don't bother.
If they're aluminum, they're worth tracking down the other parts for. You'll need backing plates and caliper "abutments", parking brake lines, and fluid lines.
If your calipers are the cast-iron ones, your brakes will probably work worse than your drums, after doing what it takes to install them. Spend money to shoot yourself in the foot in other words. Sell em to the next "greater fool" and start looking for the aluminum (PBR) setup instead.
If the calipers are cast iron, don't bother.
If they're aluminum, they're worth tracking down the other parts for. You'll need backing plates and caliper "abutments", parking brake lines, and fluid lines.
If your calipers are the cast-iron ones, your brakes will probably work worse than your drums, after doing what it takes to install them. Spend money to shoot yourself in the foot in other words. Sell em to the next "greater fool" and start looking for the aluminum (PBR) setup instead.
02-09-2016, 07:51 AM
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Car: 1987 Trans AM
Engine: 355 4-bolt, L98 heads, Holley 650DP
Transmission: 700R4
Axle/Gears: 3.70 9-bolt
Re: Adding rear disc brakes
I found this kit. Will this cover everything I need?
BW 11.6" Rear PBR disc upgrade
This kit is an OE 1LE disc conversion for '89 and earlier 9 bolt rear equipped car. Kit is complete and includes: loaded PBR caliper set, Raybestos/Delco rear rotors, new disc backing plates, new emergency brake cable set, new axle hard line set (2), new braided flex line set (3), new GM aluminum disc proportioning valve, brake line tabs and clips, all installation hardware, and an install guide to help you through it
BW 11.6" Rear PBR disc upgrade
This kit is an OE 1LE disc conversion for '89 and earlier 9 bolt rear equipped car. Kit is complete and includes: loaded PBR caliper set, Raybestos/Delco rear rotors, new disc backing plates, new emergency brake cable set, new axle hard line set (2), new braided flex line set (3), new GM aluminum disc proportioning valve, brake line tabs and clips, all installation hardware, and an install guide to help you through it
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02-09-2016, 05:36 PM
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Re: Adding rear disc brakes
No the brackets you need (aka "abutments") are unique to the PBRs. None of the parts will interchange. THIMK: ... 11.6" rotors, vs 10" ones. The calipers are like out in another whole area code.
That kit should do it, assuming it has the abutments (doesn't say)... where is it from?
That kit should do it, assuming it has the abutments (doesn't say)... where is it from?
02-10-2016, 01:24 PM
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Car: 1987 Trans AM
Engine: 355 4-bolt, L98 heads, Holley 650DP
Transmission: 700R4
Axle/Gears: 3.70 9-bolt
Re: Adding rear disc brakes
The kit is from Ed Miller at www.flynbye.com. I spoke to him yesterday and he said the kit is complete. The brackets are included in the kit. The kit comes with everything to add the full PBR system to the 9 bolt.
No the brackets you need (aka "abutments") are unique to the PBRs. None of the parts will interchange. THIMK: ... 11.6" rotors, vs 10" ones. The calipers are like out in another whole area code.
That kit should do it, assuming it has the abutments (doesn't say)... where is it from?
That kit should do it, assuming it has the abutments (doesn't say)... where is it from?
02-10-2016, 03:48 PM
#10
Re: Adding rear disc brakes
Though the backing plates are slightly different, the 9- and 10-bolt braking system is identical as far as I can recall. The following pics/part numbers may be of help:
https://www.thirdgen.org/forums/faq-...iscs-89-a.html
More info about combination valves, master cylinders and so on below:
https://www.thirdgen.org/forums/tran...-10-bolts.html
JamesC
https://www.thirdgen.org/forums/faq-...iscs-89-a.html
More info about combination valves, master cylinders and so on below:
https://www.thirdgen.org/forums/tran...-10-bolts.html
JamesC
Last edited by JamesC; 02-10-2016 at 03:58 PM. Reason: Additional info
02-12-2016, 01:47 PM
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Car: 1987 Trans AM
Engine: 355 4-bolt, L98 heads, Holley 650DP
Transmission: 700R4
Axle/Gears: 3.70 9-bolt
Re: Adding rear disc brakes
Yup, his website is still up and I placed an order. I spoke to him email a few hours later to make sure everything was good to go and estimated shipping times. He quoted me 2 weeks for shipping and said he had everything in stock.
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